US3464786A - Process for stabilizing dicalcium phosphate dihydrate - Google Patents
Process for stabilizing dicalcium phosphate dihydrate Download PDFInfo
- Publication number
- US3464786A US3464786A US551058A US3464786DA US3464786A US 3464786 A US3464786 A US 3464786A US 551058 A US551058 A US 551058A US 3464786D A US3464786D A US 3464786DA US 3464786 A US3464786 A US 3464786A
- Authority
- US
- United States
- Prior art keywords
- dicalcium phosphate
- weight
- phosphate dihydrate
- stabilizer
- stabilizing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- RBLGLDWTCZMLRW-UHFFFAOYSA-K dicalcium;phosphate;dihydrate Chemical compound O.O.[Ca+2].[Ca+2].[O-]P([O-])([O-])=O RBLGLDWTCZMLRW-UHFFFAOYSA-K 0.000 title description 38
- 238000000034 method Methods 0.000 title description 13
- 230000000087 stabilizing effect Effects 0.000 title description 5
- 239000003381 stabilizer Substances 0.000 description 24
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 16
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 15
- 235000019739 Dicalciumphosphate Nutrition 0.000 description 10
- 239000001506 calcium phosphate Substances 0.000 description 10
- NEFBYIFKOOEVPA-UHFFFAOYSA-K dicalcium phosphate Chemical compound [Ca+2].[Ca+2].[O-]P([O-])([O-])=O NEFBYIFKOOEVPA-UHFFFAOYSA-K 0.000 description 10
- 229910000390 dicalcium phosphate Inorganic materials 0.000 description 10
- 229940038472 dicalcium phosphate Drugs 0.000 description 10
- 150000001340 alkali metals Chemical class 0.000 description 8
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 8
- 229910052783 alkali metal Inorganic materials 0.000 description 7
- 238000002360 preparation method Methods 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 230000006641 stabilisation Effects 0.000 description 6
- 238000011105 stabilization Methods 0.000 description 6
- 150000004683 dihydrates Chemical class 0.000 description 5
- 235000011180 diphosphates Nutrition 0.000 description 5
- FQENQNTWSFEDLI-UHFFFAOYSA-J sodium diphosphate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-]P([O-])(=O)OP([O-])([O-])=O FQENQNTWSFEDLI-UHFFFAOYSA-J 0.000 description 5
- 235000019818 tetrasodium diphosphate Nutrition 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- JUNWLZAGQLJVLR-UHFFFAOYSA-J calcium diphosphate Chemical compound [Ca+2].[Ca+2].[O-]P([O-])(=O)OP([O-])([O-])=O JUNWLZAGQLJVLR-UHFFFAOYSA-J 0.000 description 4
- 229940043256 calcium pyrophosphate Drugs 0.000 description 4
- 235000019821 dicalcium diphosphate Nutrition 0.000 description 4
- XZTWHWHGBBCSMX-UHFFFAOYSA-J dimagnesium;phosphonato phosphate Chemical compound [Mg+2].[Mg+2].[O-]P([O-])(=O)OP([O-])([O-])=O XZTWHWHGBBCSMX-UHFFFAOYSA-J 0.000 description 4
- 238000000227 grinding Methods 0.000 description 4
- GVALZJMUIHGIMD-UHFFFAOYSA-H magnesium phosphate Chemical class [Mg+2].[Mg+2].[Mg+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O GVALZJMUIHGIMD-UHFFFAOYSA-H 0.000 description 4
- 229910000318 alkali metal phosphate Inorganic materials 0.000 description 3
- 229910000316 alkaline earth metal phosphate Inorganic materials 0.000 description 3
- 238000011065 in-situ storage Methods 0.000 description 3
- 239000004137 magnesium phosphate Substances 0.000 description 3
- 229910000400 magnesium phosphate tribasic Inorganic materials 0.000 description 3
- 229940048086 sodium pyrophosphate Drugs 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 description 3
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 2
- 150000001342 alkaline earth metals Chemical class 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000001110 calcium chloride Substances 0.000 description 2
- 229910001628 calcium chloride Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- MHJAJDCZWVHCPF-UHFFFAOYSA-L dimagnesium phosphate Chemical compound [Mg+2].OP([O-])([O-])=O MHJAJDCZWVHCPF-UHFFFAOYSA-L 0.000 description 2
- 229910000395 dimagnesium phosphate Inorganic materials 0.000 description 2
- 235000019791 dimagnesium phosphate Nutrition 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 229940048084 pyrophosphate Drugs 0.000 description 2
- -1 pyrophosphate ions Chemical class 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 235000019832 sodium triphosphate Nutrition 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 241000501754 Astronotus ocellatus Species 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 159000000007 calcium salts Chemical class 0.000 description 1
- POCPYOMYXRMNGX-UHFFFAOYSA-J calcium;disodium;phosphonato phosphate Chemical compound [Na+].[Na+].[Ca+2].[O-]P([O-])(=O)OP([O-])([O-])=O POCPYOMYXRMNGX-UHFFFAOYSA-J 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- XPPKVPWEQAFLFU-UHFFFAOYSA-J diphosphate(4-) Chemical compound [O-]P([O-])(=O)OP([O-])([O-])=O XPPKVPWEQAFLFU-UHFFFAOYSA-J 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000012065 filter cake Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 235000010994 magnesium phosphates Nutrition 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 229920000137 polyphosphoric acid Polymers 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/32—Phosphates of magnesium, calcium, strontium, or barium
- C01B25/327—After-treatment
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K8/00—Cosmetics or similar toiletry preparations
- A61K8/18—Cosmetics or similar toiletry preparations characterised by the composition
- A61K8/19—Cosmetics or similar toiletry preparations characterised by the composition containing inorganic ingredients
- A61K8/24—Phosphorous; Compounds thereof
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61Q—SPECIFIC USE OF COSMETICS OR SIMILAR TOILETRY PREPARATIONS
- A61Q11/00—Preparations for care of the teeth, of the oral cavity or of dentures; Dentifrices, e.g. toothpastes; Mouth rinses
Definitions
- the degree of stabilization is determined by means of the so-called glycerol test, wherein the DCP is pasted up with glycerol and water to give a just mobile paste, which is heated in the water bath for 30 minutes to a temperature of 100 C.
- the glycerol test is stated to be very good when, after that time, the paste is found to have an unchanged consistency. The result obtained must be considered as being insufficient when the paste is found to have hardened.
- the adjectives good, satisfactory, and sufficient are reserved to the characterization of transition grades lying between these two extremes.
- the stabilization of DCP is indispensable when it is desired substantially to reduce dehydration.
- the following compounds have inter alia been proposed for use as stabilizing agents.
- Alkali metal pyrophosphates e.g. tetrasodium pyrophosphate. They are used in a proportion of 0.5 to 1.25% by weight, referred to DCP, and they are prepared either separately in an aqueous solution to be added then to DCP, or are dissolved in the phosphoric acid necessary for preparing the DCP.
- Alkaline earth metal pyrophosphates e.g. calcium "ice pyrophosphate and magnesium pyrophosphate.
- the proportion necessary to achieve stabilization is 5% by weight for calcium pyrophosphate, and is 3% by weight for magnesium pyrophosphate.
- the calcium pyrophosphate is added to the phosphoric acid necessary for ⁇ making the DCP, whereas the magnesium pyrophosphate is prepared from MgO and pyrophosphate ions in the phosphoric acid.
- Alkali metal hexametaphosphates (l-qThese compounds are added in aqueous solution in a proportion of 0.3 to 3% by weight to the DCP in a separate operational step or during another operation, e,g, filtration.
- Alkali metal tripolyphosphates These stabilizers are used in a manner analogous to the alkali metal hexametaphosphates.
- Magnesium phosphates e.g. trimagnesium phosphate and dimagnesium phosphate. Dirnagnesium phosphate is used in a proportion of 2 to 4% by weight, the trimagnesium phosphate is used in a proportion of 0.5 to 2% by weight. In either case, the stabilization is achieved by admixing the stabilizer with dry DCP.
- the stabilizer referred to the dicalcium phosphate dihydrate
- 0.4 to 0.9% by weight, more preferably 0.8% by weight of the stabilizer, referred to the dicalcium phosphate dihydrate is added to the dicalcium phosphate during preparation, and additionally 0.2 to 0.6% by weight, advantageously 0.4 by weight, of the stabilizer is added to isolated, solid dicalcium phosphate dihydrate, and ultimately ground jointly with the solid dicalcium phosphate.
- the stabilizer portion to be added during the preparation of the dicalcium phosphate is added at a pH-value of 7.5 to 8.5, preferably at a pH-value of 8.0, and when the stabilizer portion to be added before the dicalcium phosphate is ground has a grain size approximately the same as that of the dicalcium phosphate.
- the present invention has proved especially advantageous for making stabilized dicalcium phosphate dihydrate formed of grains with a size of less than 40% from coarsely crystalline dicalcium phosphate which consists to an extent of more than 30% by weight, e.g. of 70 to by weight, of grains having a size larger than 40,14.
- the dicalcium phosphate is most advantageously admixed, during its preparation, at a pH- value of 7.5 to 8.5, with 0.4 to 019% by weight of the stabilizer, referred to the dicalcium phosphate, and the isolated, solid dicalcium phosphate dihydrate formed to an extent of more than 30% by weight of grains having a size larger than 40 is admixed then with 0.2 to 0.6% by weight of the stabilizer, referred to the dicalcium phos- TABLE II S tahilizer N arlgOy Addition prior to grinding Stabilized in reactor at pH Glycerol test 1 1.2 Sufficient.
- the pH-value was finally adjusted in a second process step while reacting the phosphoric acid in excess with calcium chloride (25-35% by weight strength) and with sodium hydroxide solution (20-50% by Wfiight strength) in stoichiometric quantitative proportions.
- the temperature in the reactor raised from initially 25-3Q C. (first step) to 40-45 C.
- the supply of calcium chloride and sodium hydroxide solution was arrested at a pH-value of 8.0. Thereafter 0.8% by "weight sodium pyrophosphate was added to achieve the stabilization.
- the finished DCP was filtered by means of a vacuum drum filter, and washed.
- the filter cake which contained about 40% by weight water of adhesion was dried in a twostage turbulent layer drier, admixed with 0.4% by weight sodium pyrophosphate, and ground in a sitter bowl mill to obtain grains of which 99.5% had a size of less than 40a.
- the sodium pyrophosphate added was formed of grains of which about to had a size larger than 40 i.e. a size approximately corresponding to that of the DCP before grinding.
- step (B) has a grain size about the same as the dicalcium phosphate dihydrate.
- step (B) is larger than 40 and the (C) step is etfected to obtain combined grain size of less than 40g.
- the stabilizer is a member selected from the group consisting of tetrasodium pyrophosphate, calcium pyrophosphate, magnesium pyrophosphate, calcium-disodium pyrophosphate, alkali metal tripolyphosphates, alkali metal hexametaphosphates, dimagnesium phosphate, and trimagnesium phosphate.
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Animal Behavior & Ethology (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- General Health & Medical Sciences (AREA)
- Inorganic Chemistry (AREA)
- Environmental & Geological Engineering (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Birds (AREA)
- Epidemiology (AREA)
- Paper (AREA)
- Cosmetics (AREA)
- Detergent Compositions (AREA)
- Materials For Medical Uses (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEK56393A DE1259861B (de) | 1965-06-16 | 1965-06-16 | Verfahren zur Herstellung von stabilisiertem Dicalciumphosphat-Dihydrat |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3464786A true US3464786A (en) | 1969-09-02 |
Family
ID=7227837
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US551058A Expired - Lifetime US3464786A (en) | 1965-06-16 | 1966-05-18 | Process for stabilizing dicalcium phosphate dihydrate |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US3464786A (enrdf_load_stackoverflow) |
| AT (1) | AT265208B (enrdf_load_stackoverflow) |
| BE (1) | BE682627A (enrdf_load_stackoverflow) |
| CH (1) | CH471038A (enrdf_load_stackoverflow) |
| DE (1) | DE1259861B (enrdf_load_stackoverflow) |
| DK (1) | DK113009B (enrdf_load_stackoverflow) |
| GB (1) | GB1089245A (enrdf_load_stackoverflow) |
| NL (1) | NL151318B (enrdf_load_stackoverflow) |
| SE (1) | SE320959B (enrdf_load_stackoverflow) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3647371A (en) * | 1968-08-07 | 1972-03-07 | Monsanto Co | Method for preparation of dicalcium phosphate |
| US4244931A (en) * | 1979-05-29 | 1981-01-13 | Monsanto Company | Dicalcium phosphate dihydrate with improved stability |
| US4247526A (en) * | 1979-05-29 | 1981-01-27 | Monsanto Company | Method for preparing dicalcium phosphate dihydrate with improved stability |
| EP0045826A1 (en) * | 1980-08-12 | 1982-02-17 | Monsanto Company | Dicalcium phosphate dihydrate having improved stability and a method for preparing it |
| US4880610A (en) * | 1988-04-20 | 1989-11-14 | Norian Corporation | In situ calcium phosphate minerals--method and composition |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2648061C2 (de) * | 1976-10-23 | 1982-11-04 | Hoechst Ag, 6000 Frankfurt | Verfahren zum Stabilisieren von Di-calciumhydrogenphosphatdihydrat |
| GB2112762B (en) * | 1981-12-31 | 1985-05-01 | Stauffer Chemical Co | Dicalcium phosphate dihydrate having improved monofluorophosphate compatibility |
| PL2222793T3 (pl) | 2007-11-19 | 2018-03-30 | Grace Gmbh & Co. Kg | Cząstki antykorozyjne |
| AR074508A1 (es) | 2008-12-08 | 2011-01-19 | Grace Gmbh & Co Kg | Particulas anticorrosivas |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2287699A (en) * | 1940-02-15 | 1942-06-23 | Monsanto Chemicals | Stabilized dicalcium phosphate |
| US3066056A (en) * | 1959-06-30 | 1962-11-27 | Victor Chemical Works | Stabilized dicalcium phosphate dihydrate |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1189527B (de) * | 1959-06-30 | 1965-03-25 | Stauffer Chemical Co | Verfahren zur Herstellung von stabilisiertem Dicalciumphosphat |
-
1965
- 1965-06-16 DE DEK56393A patent/DE1259861B/de active Pending
-
1966
- 1966-05-05 CH CH654166A patent/CH471038A/de not_active IP Right Cessation
- 1966-05-13 SE SE6652/66A patent/SE320959B/xx unknown
- 1966-05-18 US US551058A patent/US3464786A/en not_active Expired - Lifetime
- 1966-05-26 NL NL666607318A patent/NL151318B/xx not_active IP Right Cessation
- 1966-05-27 GB GB23816/66A patent/GB1089245A/en not_active Expired
- 1966-06-08 AT AT547866A patent/AT265208B/de active
- 1966-06-15 DK DK308566AA patent/DK113009B/da unknown
- 1966-06-16 BE BE682627D patent/BE682627A/xx not_active IP Right Cessation
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2287699A (en) * | 1940-02-15 | 1942-06-23 | Monsanto Chemicals | Stabilized dicalcium phosphate |
| US3066056A (en) * | 1959-06-30 | 1962-11-27 | Victor Chemical Works | Stabilized dicalcium phosphate dihydrate |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3647371A (en) * | 1968-08-07 | 1972-03-07 | Monsanto Co | Method for preparation of dicalcium phosphate |
| US4244931A (en) * | 1979-05-29 | 1981-01-13 | Monsanto Company | Dicalcium phosphate dihydrate with improved stability |
| US4247526A (en) * | 1979-05-29 | 1981-01-27 | Monsanto Company | Method for preparing dicalcium phosphate dihydrate with improved stability |
| EP0045826A1 (en) * | 1980-08-12 | 1982-02-17 | Monsanto Company | Dicalcium phosphate dihydrate having improved stability and a method for preparing it |
| US4880610A (en) * | 1988-04-20 | 1989-11-14 | Norian Corporation | In situ calcium phosphate minerals--method and composition |
Also Published As
| Publication number | Publication date |
|---|---|
| SE320959B (enrdf_load_stackoverflow) | 1970-02-23 |
| NL6607318A (enrdf_load_stackoverflow) | 1966-12-19 |
| DE1259861B (de) | 1968-02-01 |
| GB1089245A (en) | 1967-11-01 |
| AT265208B (de) | 1968-10-10 |
| BE682627A (enrdf_load_stackoverflow) | 1966-12-01 |
| CH471038A (de) | 1969-04-15 |
| NL151318B (nl) | 1976-11-15 |
| DK113009B (da) | 1969-02-10 |
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